The subject matter disclosed herein relates generally to gasification systems, and more particularly, to a system for recovering low, moderate, and/or other grades of heat from a gasification system.
Gasification systems generate syngas that can be used for power production (e.g., an integrated gasification combined cycle power plant, etc.), chemical synthesis (e.g., ethanol, methanol, ammonia, Substitute Natural Gas (SNG), Fischer-Tropsch (FT) liquids, etc.), or other purposes. For example, integrated gasification combined cycle (IGCC) power plants are capable of generating energy from various carbonaceous feedstocks, such as coal or natural gas, relatively cleanly and efficiently. Gasification systems may convert the carbonaceous feedstock, or another fuel, into a gaseous mixture of carbon monoxide (CO) and hydrogen (H2), i.e., syngas, by reaction with oxygen and steam in a gasifier. However, the syngas produced by the gasification system often needs to be cooled, and in certain configurations cleaned, before it is used. During the cleaning and/or cooling process, some thermal energy may be unused, resulting in wasted energy. Likewise, the combustion of cleaned syngas may produce thermal energy that is unused. Therefore, a system that extracts thermal energy and thereby reduces the amount of wasted thermal energy may be desirable.